Safety switch box



May 27, 1930.

p. T. WADSWORTH 1,760,571

.SAFETY SWITCH BOX Filed Dec. 9, 1925 2 Sheets-Sheet 1 May 27, 1930. D.'r. WADSWORTH SAFETY SWITCH BOX Filed Dec. 9, 1925 2 Sheets-Sheet 2amulet Davi (1T Mdsugorfh, "1W

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Patented May 27, 1930 NITED stars DAVID T. WAIDSWORTH, OF GOLD SPRINGS,KENTUCKY, ASSIGNOR TO THE WADSWORTH ELECTRIC MANUFACTURING COMPANY, OFGUVIHGTON, KENTUCKY, A CORPORA- TION OF KENTUCKY SAFETY SWITCH BOXApplication filed December This invention relates to safety switch boxesand has for an object the provision of a compact and inexpensive device.

Another object is to provide a device of the class described having anovel and simple mechanism for controlling access to the fuse chamberthereof and one which always bears a safety relation with the conditionof the switch.

Another object is to provide a device of the kind referred to in whichthe switch control lever or crank constitutes a locking means for asliding door for the fuse chamber.

Another object is to provide a device having the enumerated advantagesin which there is embodied a sliding door control which is positive,simple and economical in material and labor.

These and other objects are attained by the means described herein anddisclosed in the accompanying drawing, in which:

Fig. 1 is a fragmental perspective view of a device of my invention,showing a sliding door and switch operating handle in an operativeposition.

Fig. 2 is a similar view showing the sliding door and switch operatinghandle in an open position.

Fig. 3 is a fragmental side elevation, looking to the left of Fig. 2.

Fig. 4 is an enlarged fragmental cross section taken on line 4-4 of Fig.1.

Fig. 5 is a cross sectional view taken on line 55 of Fig. 4, parts beingbroken away.

Fig. 6 is a front elevational view of a combined switch operating anddoor locking crank of my invention.

Fig. 7 is a view looking toward the left on Fig. 6.

A switch box or cabinet 10 is provided with a cover 11 which may behingedly mounted thereon. The cover 11 has a suitable aperture 12therein of such size and shape as to provide access to the fuse sockets13 but to none of the other parts enclosed within the box. As

shown in the drawings, the fuse sockets may be disposed in a box likecompartment 14 which separates them from the lead-in, load and testterminals, as well as the switch members. A slidable door l5is mountedfor re- 9, 1325. Serial No. 74,418.

ciprocation upon the inner face of the cover 11 by means of flangedstrips 16, the outer edges of which overhang the side edges of theslidable door. A suitable lug 17 is carried by one face of the slidabledoor 15 and extends through the aperture 12 thereby providing a simplemeans for manipulating said slidable door. The lug 17 may be perforatedand a second perforate lug 18 mounted upon the cover 11 so that the fusecompartment may be locked against unauthorized access if desired. Anotch 12 in the cover 11 accommodates lug 17 when the slidable door 15is dropped to its lowermost limit of movement. The cover 11 maybe lockedand sealed by means of a suitable latch member 170 engaging integraloutwardly struck lug 180 carried by the side of the cover 11.

The locking means is provided for the slidable door 15 so as to renderthe fuse sockets inaccessible when the switch blades, such as 19, are inengagement with contacts 20'thereby closing a circuit controlled by theswitch. The slidable door cannot be opened so long as the switch remainsclosed.

The means for accomplishing the locking of the slidable door and forproviding the several safety features referred to, are embodied in anovel switch crank or throw lever shown in Figs. 6 and 7. The crankmember, indicated generally by reference numeral 21, is economicallyformed of a single section of metal rod and comprises a handle portion22 and bearing portions 23 and 24, adapted to pass through suitableperforations 25 in opposite side walls 26 of the box whereby the crankis mounted for rocking movement with handle portion 22 disposedexteriorly of said box. The bearing portion 24 isdisposed at one extremeend of the crank and is in longitudinal alignment with the bearingportion 23. Arms 26, 27 and 28 serve to position the switch rod29 andlock bar 80 in parallelism with the bearings 23 and 24 and in offsetrelation thereto. From the foregoing, it will be apparent that whenv thecrank is moved about its pivotal mounting, the rod 29 and bar 30 willmove through arcs described by arms 26 and 28 respectively. The switchblades 19 are connected to the switch rod 29 of flange 33 is by means ofinsulating members 31 suitably slotted at for receiving said rod. Byreferring to Figs. f and 7, it will be apparent that when the handle 22is pulled forward (as in Fig. 2) the rod 29 will be raised to theposition shown in full lines in Fig. 4, and bar 30 will assume a loweredposition some what removed from the sliding door 15. The slidable door15 carries a flange 33 which extends for a distance into the cabinet.lVhen the slidable door is in position for closing the aperture 12 i dcover 11, the lower end .sposed above lock bar 30 rank 21, which timethe switch ades 19 engage contacts 20. At this time, e handle portion 22assumes a vertical position. lVhen fuses are to be renewed or placed infuse sockets 13, the handle 22 is pulled forward until it abuts asuitable stop such as 35 (see Fig. 3). This movement litits rod 29through an arc and carries switch blade 19 clear of contacts 20. Theswitch is new open and the lock bar 30 has been moved arcuately downwardand out of the path of the flange 33 on slidable door 15. The slidabledoor is now free to drop clear of aperture 12 so that the fuse sockets13 are exposed.

Assuming now that the slidable door 15 is open ant. someone endeavors toclose the switch, he will immediately find that the switch handle 22cannot be moved, since, the lock bar 30 will strike the top edge of theflange 33. As soon as the door 15 is raised to completely close aperture12, the handle 22 may be pushed back to a substantially verticalposition (see Fig. 1) and rod 29 will carry the blades 19 intoengagement with the contacts and at the same time, the lock bar 30 willassume a position as shown in dotted lines in Fig. 4, in abutment withthe end 34 of flange 33, thereby precluding clownward movement of theslid able door.

Should the slidable door 15 be forced open without first having movedthe switch handle to the open position, the end 34: of flange 33 willmove the lock bar 30 and rod 29 so as to automatically open the switch.

Should an authorized person open the cover 11 and permit the slidabledoor 15 to drop, he will be unable to again close the cover 11 until theswitch 192O is opened or door 15 is raised to a closed position. Thisfeature makes it impossible to leave the box in an unsafe conditionthrough inadvertence. Lihus the box when closed and sealed alsoprecludes improper taking of the electric current from the fuse sockets33 because, due to the interlocking relation of parts, the switch mustbe in the off position before the door 15 can be opened. The fuses areso connected as to be without current when the switch is open.

The mechanism just described eliminates the need of separate lockingdevices since the switch operating crank functions as a locking means aswell as a switch operating means. This makes possible the provision of amore compact switch box structure and at the same time leaves theinterior of the box conveniently accessible for authorized workmen.

WVhat I claim is:

1. In a device of the class described the combination with a switch boxhaving an apertured cover, of a slidable door mounted for reciprocationupon the cover for opening and closing the aperture in said cover, astraight flange mounted on and terminating substantially within the bodylines of the slidable door, a switch in the box, a crank journaled inthe box for opening and closing the switch, said crank having an offsetportion for movement into and out of the path of the flange as theswitch is opened and closed by the crank.

2. In a device of the class described the combination of a switch box,an apertured cover for the box, a flanged door slidably mounted upon thecover for opening and closing the aperture in said cover, a pivotallymounted switch in the box and a crank comprising an integral rodjournaled at the sides of the box and bent to provide a throw rod formoving the switch and a lock bar for movement into and out of the pathof the flange on the sl-idable door, said lock bar being in substantialabutment with one end of the flange when the switch and door are closed.

3. In a device of the class described the com ation of a switch boxcomprising a cabinet, pivotally mounted switch blades and fuses withinthe cabinet, a flanged slidable door controlling access to the fuses anda crank pivotally mounted within the box and having an offset portionoperatively connectcd with the switch and a second offset portionadapted to move into and out of the path. of the flange, movement of thecrank in one direction serving to close the switch and lock the slidabledoor, and movement of said crank in the opposite direction serving toopen the switch and permit opening of the slidable door whereby torender accessible the fuses in the cabinet, the flange on the door andthe second mentioned ofl'set portion of the crank bearing such relationthat forcible opening of the slidable door will move the crank about itspivotal mounting for opening the switches.

at. In a switch box structure a box having an apertured cover, aslidable door control.- ling the aperture in said cover, a straightedgedflange on said cover, a switch, an externally operable crank for openingand closing the switch and having an integral offset portion adaptedwhen the door is closed to abut the end of the flange, said offsetportion being adapted, when the slidable door and switch are open toabut the edge of the flange ill) for precluding closing movement of theswitch, and latching means for rigidly securing the apertured cover tothe box to preclude opening of the cover by the crank.

5. In a switch box structure the combination of a box having anapertured cover, means for rigidly latching the cover to the box, aslidable door controlling the aperture in the cover, a straight-edgedflange on said door and terminating Within the body lines of the door, aswitch in the box, and an externally operable crank for the switchprovided with an offset portion therein which when the switch andslidable door are open abuts the edge of the flange thereby precludingclosing of the switch.

6. In a device of the class described the combination of a switch boxhaving an apertured cover, a slidable door controlling the aperture inthe cover, a depending straightedged flange on the door terminatingsubstantially at the opposite ends of the door, a switch in the box anda manually operable crank for the switch having an ofiset portionthereon adapted to abut an end of the flange when the switch and doorare closed.

7. In a device of the class described the combination of a switch box',an apertured cover for said box, a flanged slidable door for opening andclosing the aperture in the cover, a movable switch member in the boxand a switch operatingbail having an integeral bend therein constitutinga lock bar for abutting an end of the flange on the slidable door whensaid door and switch member are in closed position.

8. In a device of the class described, the combination of a switch boxhaving an apertured cover, a slidable door controlling the aperture inthe cover, an angularly disposed fiange on the door with its endssubstantially coincident with opposite ends of the door, a switch in thebox and an operating bail with a bend therein for abutting one end ofthe flange when the door and switch are closed.

9. In a device of the class described the combination of a switch boxhaving an apertured cover, a flanged slidable door controlling theaperture in the cover, a hingedly mounted switch member and an operatingbail oscillatable in the box and having bent portion for throwing theswitch memher and a second bent portion for abutting an of the flangewhen the door and switch are closed.

In testimony whereof, I have hereunto subscribed my name this 3rd day ofDecember, 1925.

DAVID T. I/VADSWORTH.

